The overall goal is to develop a methodology to define therapeutic indices for the efficacy-systemic effect of inhaled corticosteroids. Specifically, this study will: 1) obtain estimates of the degree of variability of various efficacy parameters in relation to systemic effect for two inhaled corticosteroids, specifically beclomethasone dipropionate (BUD) and fluticasone propionate (FP), and 2) develop a model that can be applied to study the efficacy/systemic effect relationship of selected inhaled lush corticosteroids. Ultimately, we would like to determine whether any of the available inhaled corticosteroids, when administered by their respective delivery systems at doses with comparable systemic effects, possess superior efficacy.